She also suggested buyers worried about potential contamination got a written response from the vendor or agent about whether there was known contamination.

She said the percentage of contaminations in homes was alarming, and people often did not do their homework before buying.

"It's not all that uncommon, unfortunately. The pressure in the market at the moment to buy instantly, whether it be at auction or otherwise, people are not willing to spend money on multiple investigations of multiple properties before they can finally secure one at the price they can pay."

Methamphetamine contamination guidelines being developed by Standards New Zealand are expected to be ready early next year.